Portion of a keyboard



FIG. 1 is a perspective view of a portion of a keyboard showing our new design;

FIG. 2 is a top view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a back view thereof; and,

FIG. 7 is a bottom view thereof.

The broken line showing of the key edges and the remainder of the keyboard is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a portion of a keyboard, as shown and described. 